Image forming device and replacement

Cross-reference to related application

This application claims priority under 35 U.S.C. .sctn.119 from Japanese Patent Application No. 2009-014663, filed on Jan. 26, 2009. The entire subject matter of the application is incorporated herein by reference.

Background

1. Technical field

Aspects of the present invention relate to an image forming device to which a replacement having a non-contact type IC tag transmitting and receiving a radio signal conveying information concerning the replacement can be detachably attachable.

2. Related art

Image forming devices configured to be able to manage replacements to be attached thereto by performing wireless communication with non-contact type IC tags held on the replacements have been widely used. Regarding such an image forming device, in order to prevent erroneously performing reading/writing information with respect to a non-contact type IC tag of a replacement which is not attached to the image forming device (e.g., a non-contact type IC tag placed outside the image forming device), the image forming device is required to distinguish a replacement attached to the image forming device from a replacement which is not attached to the image forming device.

Summary

It is possible to distinguish a replacement attached to the image forming device from a replacement not attached to the image forming device by configuring the image forming device to have attachment terminals which are electrically connected to detection contacts of the replacement in the state where the replacement is attached to the image forming device. However, even if such a configuration is adopted, a possibility remains that a contact failure occurs between the attachment terminals of the image forming device and the detection contacts of the replacement

Aspects of the present invention are advantageous in that at least one of an image forming device and a replacement configured to reliably identify the replacement attached to the image forming device is provided.

According to an aspect of the invention, there is provided an image forming device to which a replacement is detachably attachable. The replacement comprises: a non-contact type IC tag that stores data concerning the replacement and is able to transmit the data through a radio signal; a holding member that holds the non-contact type IC tag; and a shielding member formed to alter a state of the non-contact type IC tag between an exposed state where the non-contact type IC tag is exposed and a detection unit of the image forming device is able to detect the non-contact type IC tag, and a shielded state where the detection unit is not able to detect the non-contact type IC tag, by changing relatively a positional relationship with the holding member. The image forming device comprises: the detection unit configured to detect the non-contact types IC tag by receiving the radio signal transmitted from the non-contact type IC tag; a driving unit configured to drive at least one of the holding member and the shielding member to change the state of the non-contact type IC tag between the exposed state and the shielded state; and a controller that identifies the non-contact type IC tag detected by the detection unit as that provided in the replacement being attached to the image forming device in response to a fact that the non-contact type IC tag is intermittently detected by the detection unit while the driving unit is activated.

It is noted that various connections are set forth between elements in the following description. It is noted that these connections in general and unless specified otherwise, may be direct or indirect and that this specification is not intended to be limiting in this respect. Aspects of the invention may be implemented in computer software as programs storable on computer-readable media including but not limited to RAMs, ROMs, flash memory, EEPROMs, CD-media, DVD-media, temporary storage, hard disk drives, floppy drives, permanent storage, and the like.

Brief description of the accompanying drawings

FIG. 1 is a block diagram illustrating a general configuration of a printer according to an embodiment.

FIG. 2A illustrates a first example of an arrangement of a non-contact type IC tag, a holding member and a shielding member.

FIG. 2B illustrates an exposed state of the non-contact type IC tag when viewed from a side of an edge surface of the holding member.

FIG. 2C illustrates a shielded state of the non-contact type IC tag when viewed from a side of an edge surface of the holding member.

FIG. 3 is a graph illustrating an example of a detection pattern of the non-contact type IC tag.

FIG. 4A illustrates a second example of an arrangement of the non-contact type IC tag, the holding member and the shielding member.

FIG. 4B illustrates an exposed state of the non-contact type IC tag when viewed from a side of an edge surface of the holding member.

FIG. 4C illustrates a shielded state of the non-contact type IC tag when viewed from a side of an edge surface of the holding member.

FIG. 5A illustrates a third example of an arrangement of the non-contact type IC tag, the holding member and the shielding member.

FIG. 5B illustrates an exposed state of the non-contact type IC tag when viewed from a side of an edge surface of the holding member.

FIG. 5C illustrates a shielded state of the non-contact type IC tag when viewed from a side of an edge surface of the holding member.

FIG. 6A illustrates a fourth example of an arrangement of the non-contact type IC tag, the holding member and the shielding member.

FIG. 6B is a graph illustrating a detection pattern of the non-contact type IC tag in the arrangement shown in FIG. 6A.

FIG. 7 is a flowchart illustrating a first example of a detection process to be executed by a control unit of the printer.

FIG. 8 is a flowchart illustrating a second example of a detection process to be executed by a control unit of the printer.

FIG. 9 is a flowchart illustrating a third example of a detection process to be executed by a control unit of the printer.

FIG. 10 is a flowchart illustrating a fourth example of a detection process to be executed by a control unit of the printer.

FIGS. 11A and 11B are flowcharts as examples of a deletion process for deleting a detection exception list.

Detailed description

Hereafter, an embodiment according to the invention will be described with reference to the accompanying drawings.

As shown in FIG. 1, a printer 1 according to an embodiment includes a control unit 11, a non-volatile memory 12, an operation unit 13, a display panel 14, a recordation unit 15, a wireless communication unit 16, and a communication interface 17 used to communicate with external devices, such as a device on a network or a device locally connected thereto.

The control unit 11 is implemented, for example, by a microcomputer chip in which a CPU, a RAM and a ROM are embedded. The control unit 11 totally controls the printer 1. The control unit 11 executes a print process for printing an image on a recording medium based on print data received, for example, from an information processing device, via the communication interface 17. The non-volatile memory 12 stores programs and various types of data for achieving the functions of the printer 1. The operation unit 13 includes a plurality of keys to be operated by a user. The display panel 14 is, for example, a liquid crystal panel on which various types of information is displayed.

The recordation unit 15 forms an image on a recording medium, such as a sheet of paper. The recordation unit 15 is configured such that image formation units can be detachably attachable to the recordation unit 15. The image formation units (i.e., replacements) detachably attachable to the recordation unit 15 include, for example, a paper supply cartridge which accommodates sheets of paper, a drum cartridge which transfers developer (e.g., toner) to a sheet of paper, and a developer cartridge which accommodates developer (e.g., toner). It should be noted that although in FIG. 1 only one replacement 21 (which is detachably attachable to the recordation unit 15) is illustrated, practically more than one cartridge type replacement can be detachably attachable to the recordation unit 15.

If the replacement 21 to be attached to the recordation unit 15 is the paper supply cartridge, the replacement 21 has a paper supply roller. If the replacement 21 is the drum cartridge, the replacement 21 has a photosensitive drum or a transfer roller. If the replacement 21 is the developer cartridge, the replacement 21 has a developer supply roller. That is, each type of replacement has a rotational member for achieving the function of each replacement. Accordingly, the recordation unit 15 has a driving unit 151 which rotates each rotational member of the replacement 21 with a motor driven by an on/off signal output by the control unit 11. That is, in the state where the replacement 21 is attached to the recordation unit 15, the driving force of the driving unit 151 of the recordation unit 15 is transmitted to the rotational member of the replacement 21 (see arrows in FIG. 1).

On the other hand, the replacement 21 is provided with a non-contact type IC tag (RFID tag) 31, a holding member 22 which holds the non-contact type IC tag 31, a shielding member 23 which alters a state of the non-contact type IC tag 31 between an exposed state where the non-contact type IC tag 31 is exposed to be read by the wireless communication unit 16 and a shielded state where the non-contact type IC tag 31 is shielded by the shielding member 23 not to be read by the wireless communication unit 16.

The non-contact type IC tag 31 stores identification information (ID) and specifications of the replacement 21, and is able to transmit such information stored therein through wireless communication with the wireless communication unit 16. Furthermore, the non-contact type IC tag 31 is able to stored information received from the wireless communication unit 16 of the printer 1.

One of the shielding member 23 and the holding member 22 holding the non-contact type IC tag 31 is formed integrally with a rotation shaft of each roller of the replacement 21 or is configured to be rotatable in conjunction with the rotation shaft of the replacement 21. In this configuration, when the roller of the replacement 21 is rotated by the driving unit 151, a positional relationship between the holding member 22 and the shielding member 23 changes in response to rotation of the roller, and therefore the state of the non-contact type IC tag 31 alternately alters between the exposed state and the shielded state. Details (e.g., motions and shapes) of the holding member 22 and the shielding member 23 will be explained later.

The wireless communication unit 16 is configured as an IC reader and writer which, under control of the control unit 11, reads data from and writes data to the non-contact type IC tag 31 provided in the replacement 21 attached to the recordation unit 15.

As described in detail below, the printer 1 is configured such that based on the ID and the specifications read from the non-contact type IC tag 31 provided in the replacement 21 attached to the printer 1, the printer 1 manages the replacement 21. When a plurality of types of replacements are attached to the printer 1, the printer 1 identifies each replacement by detecting ID of each replacement.

It is required to prevent erroneously detecting a non-contact type IC tag of a replacement which is placed within a wireless communication range but is not attached to the printer 1, and thereby erroneously judging that the replacement including such a non-contact type IC is attached to the printer 1. For this reason, the printer 1 according to the embodiment is configured to be able to reliably distinguish a replacement attached to the printer 1 from a replacement not attached to the printer 1 as described below.

Hereafter, the holding member 22 and the shielding member 23 are explained in detail by providing four types of examples (1.sup.st to 4.sup.th Examples) of the holding member 22 and the shielding member 23.

1.sup.st Example

In the 1.sup.st example, the holding member 22 is configured to rotate, and the shielding member 23 is fixed (see FIGS. 2A to 2C). As shown in FIG. 2A, on a side surface of the replacement 21, a roller shaft is protruded, and a rotatable holding member (holding member 22) is formed by an end portion of the roller shaft. On an outer circumferential surface of a cylindrical shape of the holding member 22, the non-contact type IC tag 31 is held. The holding member 22 rotates about a rotation axis shown in FIG. 2A in accordance with rotation of the roller of the replacement 21. Therefore, the non-contact type IC tag 31 held on the outer circumferential surface of the holding member 22 rotates about the rotation axis with rotation of the holding member 22.

The holding member 22 is made of material (e.g., metal) which shields a radio wave transmitted and received by the non-contact type IC tag 31. Therefore, the non-contact type IC tag 31 has such directivity that the non-contact type IC tag 31 is able to communicate only on the front side of the non-contact type IC tag 31.

The shielding member 23 has a cylindrical shape having an inner diameter which is slightly larger than an outer diameter of the cylindrical shape of the holding member 22. Further, the shielding member 23 is formed such that a part of the cylindrical shape is removed along an axis of the cylindrical shape. That is, the shielding member 23 has a cross sectional shape having a form of a letter "C". The shielding member 23 is fixed to a casing of the replacement 21 such that a center axis of the cylindrical shape of the shielding member 23 coincides with the rotation axis of the holding member 22, and that a cylindrical inner surface of the shielding member 23 surrounds an outer circumferential surface of the holding member 22.

The shielding member 23 is made of material (e.g., metal) which shields a radio wave transmitted and received by the non-contact type IC tag 31. Therefore, by covering the front side of the non-contact type IC tag 31 held on the holding member 22 with a part of the shielding member 23 other than the removed part, it is possible to move the wireless condition to a state where the wireless communication unit 16 is unable to detect the non-contact type IC tag 31.

In the above described configuration regarding the holding member 22 and the shielding member 23, when the holding member 22 (provided to be rotatable) is rotated to move the non-contact type IC tag 31 relative to the shielding member 23, the positional relationship of the holding member 22 and the shielding member 23 repeatedly alters between the state where the non-contact type IC tag 31 is covered by the shielding member 23 and the state where the non-contact type IC tag 31 is exposed through the removed part of the shielding member 23.

As shown in FIG. 2B, when the front side of the non-contact type IC tag 31 is situated at the removed part of the shielding member 23, the non-contact type IC tag 31 is in an exposed state where the wireless communication unit 16 of the printer 1 is able to detect and read the non-contact type IC tag 31. On the other hand, as shown in FIG. 2C, when the non-contact type IC tag 31 is covered by the shielding member 23, the non-contact type IC tag 31 is in a shielded state where the wireless communication 16 of the printer 1 is unable to detect and read the non-contact type IC tag 31 because in this case a radio wave is shielded by the shielding member 23 and the holding member 22.

In the above described configuration, by rotating the holding member 22 at a constant speed by the driving unit 151, a detection pattern of a radio signal of the non-contact type IC tag 31 by the wireless communication unit 16 becomes a pattern shown in FIG. 3. As shown in FIG. 3, during a time period where the driving unit 151 is activated, the radio wave of the non-contact type IC tag 31 is detected each time the non-contact type IC tag 31 makes one rotation together with the holding member 22. By continuing rotations of the holding member 22, the detection pattern shown in FIG. 3 where a short time of detection appears repeatedly is obtained.

2.sup.nd Example

In the 2.sup.nd example, the holding member 22 is fixed, and the shielding member 23 is rotatable (see FIGS. 4A to 4C).

As shown in FIG. 4A, on a side surface of the replacement 21, a roller shaft is protruded, and a rotatable shielding member (the shielding member 23) is formed by an end portion of the roller shaft. The shielding member 23 has a cylindrical shape having an inner diameter which is slightly larger than an outer diameter of a cylindrical shape of the holding member 22. Further, the shielding member 23 is formed such that a part of a cylindrical shape is removed along an axis of the cylindrical shape. That is, the shielding member 23 has a cross sectional shape having a form of a letter "C".

Further, the shielding member 23 is located such that an inner circumferential surface thereof surrounds the circumferential surface of the cylindrical holding member 22. The shielding member 23 is provided to rotate about a rotation axis shown in FIG. 4A in accordance with rotation of the roller of the replacement 21. That is, the shielding member 23 rotates around the holding member 22. The shielding member 23 is made of material (e.g. metal) which is able to shield a radio wave transmitted and received by the non-contact type IC tag 31. Therefore, by covering the front side of the non-contact type IC tag 31 held on the holding member 22 with a part of the shielding member 23 other than the removed part, it is possible to move the wireless condition to a state where the wireless communication unit 16 is unable to detect the non-contact type IC tag 31.

On the other hand, the holding member 22 holds the non-contact type IC tag 31 on the outer circumferential surface of the cylindrical shape thereof. The holding member 22 is positioned such that the center axis of the cylindrical shape thereof coincides with the rotation axis of the shielding member 23, and further the holding member 22 is fixed to a casing of the replacement 21 in a state where the outer circumferential surface thereof is surrounded by the shielding member 23. The holding member 22 is made of material (e.g., metal) which is able to shield a radio wave transmitted and received by the non-contact type IC tag 31. Therefore, the non-contact type IC tag 31 has such directivity that the non-contact type IC tag 31 is able to communicate only on the front side of the non-contact type IC tag 31.

In the above described configuration regarding the holding member 22 and the shielding member 23, when the shielding member 23 (provided to be rotatable) is rotated to move relative to the non-contact type IC tag 31, the positional relationship of the holding member 22 and the shielding member 23 repeatedly alters between the state where the non-contact type IC tag 31 is covered by the shielding member 23 and the state where the non-contact type IC tag 31 is exposed through the removed part of the shielding member 23.

As shown in FIG. 4B, when the removed part of the shielding member 23 is moved to the position at which the non-contact type IC tag 31 is held and thereby the non-contact type IC tag 31 is brought to the exposed state where the front side of the non-contact type IC tag 31 is exposed through the removed part of the shielding member 23, the wireless communication unit 16 of the printer 1 becomes able to detect and read the non-contact type IC tag 31.

On the other hand, as shown in FIG. 4C, when the non-contact type IC tag 31 is covered by the shielding member 23, the non-contact type IC tag 31 is brought to the shielded state where the wireless communication 16 of the printer 1 is unable to detect and read the non-contact type IC tag 31 because in this case a radio wave is shielded by the shielding member 23 and the holding member 22.

In the above described configuration, by rotating the shielding member 23 at a constant speed by the driving unit 151, a detection pattern of a radio signal of the non-contact type IC tag 31 by the wireless communication unit 16 becomes a pattern shown in FIG. 3. As shown in FIG. 3, during a time period where the driving unit 151 is activated, the radio wave of the non-contact type IC tag 31 is detected each time the non-contact type IC tag 31 makes one rotation together with the shielding member 23. By continuing rotations of the shielding member 23, the detection pattern shown in FIG. 3 where short time detection appears repeatedly is obtained.

3.sup.rd Example

In the following, the 3.sup.rd example of the configurations of the holding member 22 and the shielding member 23 is explained. In the 3.sup.nd example which is different from the first and second examples, the holding member 22 is rotatable and the shielding member 23 is fixed, and in this configuration the state of the non-contact type IC tag 31 alters between the exposed state and the shielded state (see FIGS. 5A to 5C).

As shown in FIG. 5A, on a side surface of the replacement 21, a roller shaft is protruded, and a rotatable holding member (holding member 22) is formed by an end portion of the roller shaft. The holding member 22 hold the non-contact type IC tag 31 on an end face of a cylindrical part thereof, and rotates about a rotation axis shown in FIG. 5A with rotation of a roller in the replacement 21.

More specifically, the non-contact type IC tag 31 is located on the end face of the cylindrical part at a position shifted from the rotation axis toward the periphery side, so that the non-contact type IC 31 rotates about the rotation axis in accordance with rotation of the holding member 22. The holding member 22 is made of material (e.g., metal) which is able to shield a radio wave transmitted and received by the non-contact type IC tag 31. Therefore, the non-contact type IC tag 31 held on the holding member 22 has such directivity that the non-contact type IC tag 31 is able to communicate only on the front side of the non-contact type IC tag 31.

On the other hand, the shielding member 23 has a cylindrical shape whose inner diameter is slightly larger than the outer diameter of the holding member 22. The shielding member 23 is a lid-like member configured such that one of open ends thereof is covered by a lid plate. The shielding member 23 is positioned such that the center axis of the cylindrical shape thereof coincides with the rotation axis of the holding member 22, and is fixed to a casing of the replacement 21 such that the end face and the outer circumferential surface of the holding member 22 are covered by the cylindrical inner surface and the inner surface of the lid plate of the shielding member 23.

Furthermore, a hole (a detection window 231) is formed in the lid plate of the shielding member 23. More specifically, the detection window 231 is located at a position along a track of rotational movement of the non-contact IC tag 31 about the rotation axis, and is formed to have a size enabling the entire non-contact type IC 31 to be exposed through the detection window 231.

The shielding member 23 is made of material (e.g., metal) which is able to shield a radio wave transmitted and received by the non-contact type IC tag 31. By covering the non-contact type IC tag 31 held on the holding member 22 with a part of the shielding member 23 other than a part of the detection window 231, the shielding member 23 changes the wireless condition to a state where the wireless communication unit 16 is unable to detect the non-contact type IC tag 31.

In the above described configuration regarding the holding member 22 and the shielding member 23, when the holding member 22 (provided to be rotatable) is rotated to move the non-contact type IC tag 31 relative to the shielding member 23, the positional relationship of the holding member 22 and the shielding member 23 repeatedly alters between the state where the non-contact type IC tag 31 is covered by the shielding member 23 and the state where the non-contact type IC tag 31 is exposed through the detection window 231.

As shown in FIG. 5A, when the holding member 22 rotates about the center axis and thereby the non-contact type IC tag 31 is moved to the position where the non-contact type IC tag 31 is exposed through the detection window 231 of the shielding member 23, the non-contact type IC tag 31 is brought to the exposed state where the wireless communication unit 16 of the printer 1 is able to detect and read the non-contact type IC tag 31.

On the other hand, as shown in FIG. 5B, when the holding member 22 rotates about the rotation axis and thereby the non-contact type IC tag 31 is moved to the state where the non-contact type IC tag 31 is covered by the shielding member 23, the non-contact type IC tag 31 is brought to the shielded state where the wireless communication 16 of the printer 1 is unable to detect and read the non-contact type IC tag 31 because in this case a radio wave is shielded by the shielding member 23 and the holding member 22.

In the above described configuration of the replacement 21, by rotating the holding member 22 at a constant speed by the driving unit 151, a detection pattern of a radio signal of the non-contact type IC tag 31 by the wireless communication unit 16 becomes a pattern shown in FIG. 3. As shown in FIG. 3, during a time period where the driving unit 151 is activated, the radio wave of the non-contact type IC tag 31 is detected each time the non-contact type IC tag 31 makes one rotation together with the shielding member 23. By continuing rotations of the shielding member 23, the detection pattern shown in FIG. 3 where short time detection appears repeatedly is obtained.

4.sup.th Example

In the following, the 4.sup.th example of the configurations of the holding member 22 and the shielding member 23 is explained. The 4.sup.th example is a variation of the 3.sup.rd example. In the 4.sup.th example, a plurality of detection windows 231 are formed in the lid plate of the shielding member 23 (see FIG. 6A).

As shown in FIG. 6A, two holes (detection widows 231) are formed in the lid plate of the shielding member 23 which covers the rotatable holding member 22. The two detection windows 231 are formed along a track of rotation of the non-contact type IC tag 31.

When the holding member 22 is rotated at a constant speed by the driving unit 151 in this configuration of the replacement 21, a detection pattern of a radio signal of the non-contact type IC tag 31 by the wireless communication unit 16 becomes a pattern shown in FIG. 6B. As shown in FIG. 6B, during a time period where the driving unit 151 is activated, the radio wave of the non-contact type IC tag 31 is detected two times for one rotation of the holding member 22 and the non-contact type IC tag 31. By continuing rotations of the holding member 22, the detection pattern shown in FIG. 6B where two-time detection per one rotation cycle appears repeatedly is obtained.

It is understood that by increasing the number of detection windows 231 of the shielding member 23, it becomes possible to increase counts of detection for one rotation cycle. It is also possible to change timing of detection of a radio signal within one rotation cycle by changing a positional relationship between the detection windows 231. In other words, by varying the number of detection windows and positions of detection windows, it becomes possible to provide a unique detection pattern for each replacement 21. It is also possible to configure the printer 1 to be able to identify the type of the replacement 21 by differentiating the detection patterns among the replacements as described above.

Hereafter, four examples (detection processes

to (4)) of a detection process for identifying the replacement 21 attached to the printer 1 are explained. The detection processes

to

are executed under control of the control unit 11 with the above described 1st to 4th examples of the configuration of the holding member 22 and the shielding member 23, respectively. In the following, an expression like "rotate the driving unit 151" means that one of the holding member 22 and the shielding member 23 provided to be rotatable is rotated by rotating the driving unit 151 so that the state of the non-contact type IC tag 31 is altered between the exposed state and the shielded state.

Detection Process

The detection process

shown in FIG. 7 is executed at predetermined timing when identification of the replacement 21 attached to the printer 1 is required. For example, the predetermined timing includes timing when the printer 1 is turned on, and timing when an opening or closing operation for a cover used to replace the replacement 21 attached to the printer 1 is detected.

First, the control unit 11 operates to detect identification of the non-contact type IC tag 31 through the wireless communication unit 16 for a predetermined time period in a state where the driving unit 151 is stopped (step S101). Detection of the identification of the non-contact type IC tag 31 is executed by continuously transmitting, from the wireless communication unit 16, a request signal for requesting a replay to non-contact type IC tags 31 existing within a communication range, and by receiving identification transmitted from the non-contact type IC tags existing within the communication range. It should be noted that the non-contact type IC tags within the communication range include the non-contact type IC tag 31 in the inside of the printer 1 and the non-contact type IC tag 31 in another printer.

In step S101, when an ID equal to one of IDs registered in a detection exception list is detected, such an ID is neglected. That is, even when such an ID in the detection exception list is detected, the control unit 11 judges that no ID is detected.

Next, in step S102, the control unit 11 judges whether an ID of the non-contact type IC tag 31 is detected based on a result of the detection for the predetermined time period in step S101. When the control unit 11 judges that an ID is detected (S102: YES), control proceeds to step S103 where the control unit 11 judges whether a detection pattern of the ID is a periodic pattern.

If the ID is periodically detected even when the driving unit 151 is stopped, it can be judged that an ID of the non-contact type IC tag 31, whose alternating state between the exposed state and the shielded state is being detected in another printer existing around the printer 1, is detected in the printer 1. Therefore, in this case (S103: YES), the control unit 11 judges that the replacement 21 corresponding to the periodically detected ID is not a replacement attached to the printer 1, and registers such an ID in the detection exception list (step S104). Then, control returns to step S101. The detection exception list is a list of IDs of replacements 21 which are regarded as not being attached to the printer 1. IDs registered in the detection exception list are treated as targets to be excepted from detection results by the wireless communication unit 16.

When the control unit 11 judges that no ID of the non-contact type IC tag 31 is detected (S102: NO), or the control unit 11 judges that the ID of the non-contact type IC tag 31 is not periodically detected but is detected continuously (S103: NO), control proceeds to step S105 where the control unit 11 outputs a signal for turning on the driving unit 151 to start rotation (step S105). By starting to rotate the driving unit 151, the state of the non-contact type IC tag 31 of the replacement 21 attached to the printer 1 starts to alter between the exposed state and the shielded state.

Then, the control unit 11 judges whether an ID of the non-contact type IC tag 31 being rotated by the driving unit 151 is detected (step S106). It should be noted that when an ID equal to an ID registered in the detection exception list is detected, the control unit 11 neglects such an ID registered in the detection exception list. On the other hand, when the control unit 11 judges that no ID of the non-contact type IC tag 31 is detected (S106: NO), the control unit 11 judges whether a predetermined time has elapsed (i.e., whether timeout occurs) (step S108). When the predetermined time has not elapsed (S108: NO), control returns to step S106.

When the control unit 11 judges that an ID of the non-contact type IC tag 31 is detected (S106: YES), control proceeds to step S107 where the control unit 11 judges whether a detection pattern of the ID is periodic.

When the control unit 11 judges that the detection patter is not periodic but is continuous (S107: NO), control proceeds to step S108 to make a judgment regarding a lapse of the timeout as described above.

When the ID is detected periodically in step S107 (S107: YES), control proceeds to step S109 where the control unit 11 judges whether IDs of a plurality of non-contact type IC tags 31 are detected periodically. More specifically, in step S109, when the printer 1 is configured such that a plurality of replacements 21 can be attached at the same time, the control unit 11 judges whether a plurality of IDs are detected, and further judges whether the detected plurality of IDs indicate the same type of replacement.

When a plurality of IDs are not detected or when all the detected plurality of IDs indicate different types of replacements, the judgment result in step S109 becomes "NO". On the other hand, when a plurality of IDs are detected and the detected IDs include IDs indicating the same type of replacement, the judgment result in step S109 becomes "YES".

If it is judged in step S109 that the control unit 11 detects a single ID periodically, but not the plurality of non-contact types IC tags (S109: NO), the control unit 11 judges that the detected ID is the ID of the replacement 21 attached to the printer 1 (step S110). Then, the control unit 11 outputs a signal for turning off to the driving unit 151 to stop the rotation of the driving unit 151 (step S111). Then, the detection process

terminates.

It should be noted that when the control unit 11 stops the driving unit 151, the control unit 11 controls the rotation angle of the motor so the non-contact type IC tag 31 of the replacement 21 is brought to the shielded state. As a result, a possibility, that the non-contact type IC tag 31 of the replacement 21 attached to the printer 1 is detected when the detection is made next in a state where the driving unit 151 is stopped, becomes low, and thereby it becomes easier to identify the replacement 21 not attached to the printer 1, with exception of the case where power of the printer 1 is accidentally cut off while the driving unit 151 is rotated.

On the other hand, when it is judged in step S108 that the timeout occurs in a state where no ID of the non-contact type IC tag 31 has been detected from the beginning of rotation of the driving unit 151 in step S105 (S106: NO) or when it is judged in step S108 that the occurs in a state where an ID is detected continuously (S107: NO), control proceeds to step S112. In step S112, the control unit 11 judges that no replacement 21 is connected to the printer 1. If an ID has been detected in step S112, the control unit 11 may register such an ID in the detection exception list. After step S112 is processed, the control unit 11 outputs a power off signal to the driving unit 151 to stop rotation of the driving unit 151 (step S111). Then, the detection process

terminates.

On the other hand, when the control unit 11 judges in step S109 that IDs of the plurality of non-contact type IC tags 31 are detected periodically while the driving unit 151 rotates (S109: YES), the control unit 11 outputs a power off signal to the driving unit 151 to stop rotation of the driving unit 151 (step S113). In this case, the control unit 11 controls the motor of the replacement 21 so that the non-contact type IC tag 31 of the replacement is brought to the shielded state.

Detecting periodically the IDs of the plurality of non-contact type IC tags 31 during rotation of the driving unit 151 means that the control unit 11 has detected not only the non-contact type IC tag 31 of the replacement 21 attached to the printer 1 but also the non-contact type IC tag provided in another printer in which the ID is detected while rotating the driving unit. Therefore, in this case, it is necessary to identify whether the detected ID is the ID of the replacement 21 attached to the printer 1 or the ID of the replacement attached to another printer.

For this reason, first, the control unit 11 stops the driving unit 151 of the printer 1 (i.e., its own driving unit 151) (step S113), and sets a randomly selected detection time (step S114). Then, control returns to step S101 to try to detect the ID of the non-contact type IC tag 31 during the detection time set in step S114 while stopping the driving unit 151. If the ID is periodically detected during the detection time (S103: YES), the control unit 11 judges that the replacement 21 corresponding to the detected ID is a replacement not attached to the printer 1, and in this case the control unit 11 registers the detected ID in the detection exception list (step S104). As a result, the wireless condition moves to a state where non-contact IC tags 31 of the replacements 21 attached to other printers are not detected. Therefore, it becomes possible to identify an ID of the replacement 21 attached to the printer 1 through steps S101 to S111.

If the control unit 11 were not able to periodically detect the non-contact type IC tag 31 within the detection time set in step S114 (S013: NO), it can be judged that rotation of the driving unit 151 of another printer has been stopped. Therefore, in this case, it becomes possible to identify the ID of the replacement 21 attached to the printer 1 through steps S101 to S111.

Detection Process

As in the case of the detection process (1), the detection process

shown in FIG. 8 is executed at predetermined timing when identification of the replacement 21 attached to the printer 1 is required. For example, the predetermined timing includes timing when the printer 1 is turned on, and timing when an opening or closing operation for a cover used to replace the replacement 21 attached to the printer 1 is detected. Since steps S201 to S212 of the detection process

are substantially the same as steps S101 to S112 of the detection process

shown in FIG. 7, explanations thereof will not be repeated. In the following, steps S213 to S215 after the affirmative judgment in step S209 will be explained.

When the control unit 11 judges in step S209 that IDs of the plurality of non-contact type IC tags 31 are detected during rotation of the driving unit 151 (S209: YES), the control unit 11 sets a randomly selected detection time (step S213). It should be noted that step S213 is executed only for the first loop process, and is skipped from the second and subsequent loop processes.

Detecting the IDs of the plurality of non-contact type IC tags 31 during rotation of the driving unit 151 means that the control unit 11 has detected not only the non-contact type IC tag 31 of the replacement 21 attached to the printer 1 but also the non-contact type IC tag provided in another printer in which the ID is detected while rotating the driving unit. Therefore, in this case, it is necessary to identify whether the detected ID is the ID of the replacement 21 attached to the printer 1 or the ID of the replacement attached to another printer.

The description continues in the full USPTO document.